While the game is running, open Task Manager. Find the process, right-click it, select "Set Affinity," and limit the game to only 4 or 8 CPU cores.
If the standard permission fixes fail, creating a fresh local Windows account often resolves deep-seated permission conflicts that prevent saving. : prototype 2 failed to save data fix exclusive
Third-party antivirus (e.g., Avast, McAfee, Norton) may block writes to Documents. While the game is running, open Task Manager